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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CDT Sun Oct 27 2024 Valid 271630Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...Synopsis and Discussion... Strong height falls will occur across the Pacific Northwest today as a shortwave trough moves eastward over this region. Cooling temperatures aloft will encourage steepening mid-level lapse rates as thermodynamic profiles gradually become favorable for isolated weak convection. Various NAM/RAP forecast soundings suggest parcels could attain heights necessary for occasional lighting discharge by late this morning into the afternoon, with continued thunderstorm potential this evening and overnight. Convection along/near a surface front in southeast AR and northern MS will remain capable of producing isolated lightning in the short term given the presence of weak MUCAPE. Even though large-scale ascent will remain weak, additional thunderstorms may develop this afternoon farther south along/near the front as daytime heating occurs across parts of the ArkLaTex. A low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. Based on where a surface front is currently located, this feature should support convection generally remaining off the SC Coast, where low-level convergence and instability will be maximized over the Gulf Stream. ..Gleason/Wendt.. 10/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Sun Oct 27 2024 Valid 271300Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, but isolated thunderstorms may occur along the coastal Pacific Northwest and coastal Carolinas. ...Discussion... Strong height falls will develop across the Pacific Northwest today in response to an approaching and amplifying shortwave trough. Cooling temperatures aloft will encourage steepening lapse rates as thermodynamic profiles become more favorable for weak convection within the developing onshore flow regime. Forecast soundings suggest parcels could attain heights necessary for lighting discharge by late morning into afternoon. Across the Carolinas, a low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. This feature may influence isolated weak convection near the coast where low-level convergence will be maximized. Additionally, weak elevated instability will develop along the cool side of the boundary, and forecast soundings exhibit adequate buoyancy and lapse rates for parcels to potentially reach levels required for lightning. A few lightning flashes may also occur mainly this morning across parts of the Mid-South and Lower Mississippi Valley. ..Guyer.. 10/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Sun Oct 27 2024 Valid 271300Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, but isolated thunderstorms may occur along the coastal Pacific Northwest and coastal Carolinas. ...Discussion... Strong height falls will develop across the Pacific Northwest today in response to an approaching and amplifying shortwave trough. Cooling temperatures aloft will encourage steepening lapse rates as thermodynamic profiles become more favorable for weak convection within the developing onshore flow regime. Forecast soundings suggest parcels could attain heights necessary for lighting discharge by late morning into afternoon. Across the Carolinas, a low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. This feature may influence isolated weak convection near the coast where low-level convergence will be maximized. Additionally, weak elevated instability will develop along the cool side of the boundary, and forecast soundings exhibit adequate buoyancy and lapse rates for parcels to potentially reach levels required for lightning. A few lightning flashes may also occur mainly this morning across parts of the Mid-South and Lower Mississippi Valley. ..Guyer.. 10/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Sun Oct 27 2024 Valid 271300Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, but isolated thunderstorms may occur along the coastal Pacific Northwest and coastal Carolinas. ...Discussion... Strong height falls will develop across the Pacific Northwest today in response to an approaching and amplifying shortwave trough. Cooling temperatures aloft will encourage steepening lapse rates as thermodynamic profiles become more favorable for weak convection within the developing onshore flow regime. Forecast soundings suggest parcels could attain heights necessary for lighting discharge by late morning into afternoon. Across the Carolinas, a low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. This feature may influence isolated weak convection near the coast where low-level convergence will be maximized. Additionally, weak elevated instability will develop along the cool side of the boundary, and forecast soundings exhibit adequate buoyancy and lapse rates for parcels to potentially reach levels required for lightning. A few lightning flashes may also occur mainly this morning across parts of the Mid-South and Lower Mississippi Valley. ..Guyer.. 10/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Sun Oct 27 2024 Valid 271300Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, but isolated thunderstorms may occur along the coastal Pacific Northwest and coastal Carolinas. ...Discussion... Strong height falls will develop across the Pacific Northwest today in response to an approaching and amplifying shortwave trough. Cooling temperatures aloft will encourage steepening lapse rates as thermodynamic profiles become more favorable for weak convection within the developing onshore flow regime. Forecast soundings suggest parcels could attain heights necessary for lighting discharge by late morning into afternoon. Across the Carolinas, a low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. This feature may influence isolated weak convection near the coast where low-level convergence will be maximized. Additionally, weak elevated instability will develop along the cool side of the boundary, and forecast soundings exhibit adequate buoyancy and lapse rates for parcels to potentially reach levels required for lightning. A few lightning flashes may also occur mainly this morning across parts of the Mid-South and Lower Mississippi Valley. ..Guyer.. 10/27/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Sun Oct 27 2024 Valid 271300Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today, but isolated thunderstorms may occur along the coastal Pacific Northwest and coastal Carolinas. ...Discussion... Strong height falls will develop across the Pacific Northwest today in response to an approaching and amplifying shortwave trough. Cooling temperatures aloft will encourage steepening lapse rates as thermodynamic profiles become more favorable for weak convection within the developing onshore flow regime. Forecast soundings suggest parcels could attain heights necessary for lighting discharge by late morning into afternoon. Across the Carolinas, a low-amplitude shortwave trough will spread southeastward across the southern Appalachians during the late afternoon. This feature may influence isolated weak convection near the coast where low-level convergence will be maximized. Additionally, weak elevated instability will develop along the cool side of the boundary, and forecast soundings exhibit adequate buoyancy and lapse rates for parcels to potentially reach levels required for lightning. A few lightning flashes may also occur mainly this morning across parts of the Mid-South and Lower Mississippi Valley. ..Guyer.. 10/27/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Sun Oct 27 2024 Valid 301200Z - 041200Z ...DISCUSSION... ...Wednesday/Day 4 and Thursday/Day 5... An upper-level trough is forecast to move eastward into the central Rockies and northern Plains on Wednesday, as an associated mid-level jet translates eastward into the mid Missouri Valley. At the surface, a cold front is forecast to move east-southeastward across the Upper Midwest and central Plains. Scattered thunderstorm development is expected along and ahead of the front during the afternoon. Sufficient instability combined with strong low-level flow, and lift associated with the upper-level trough will be favorable for severe storms across parts of the region. The most favorable area for severe storms appears to be from north Texas and Oklahoma northeastward into western and northern Missouri. GFS forecast soundings along this corridor during the late afternoon suggest that MLCAPE will peak in the 1000 to 1500 J/kg range. 0-6 km shear is forecast to be between 40 and 50 knots, with 700-500 mb lapse in the 7 to 7.5 C/km range. If this environement can materialize, supercell development with large hail and severe wind gusts could occur. A chance for very large hail will be possible with the more intense cells. An isolated tornado threat also appears possible. On Thursday, the upper-level trough is forecast to move into the Great Lakes region, as the cold front advances southeastward into the Ohio Valley and Ark-La-Tex. Isolated strong to severe storms will be possible along parts of the front where surface temperatures are able to warm sufficiently. The strongest low to mid-level flow is forecast over the mid Mississippi and lower Ohio Valley suggesting that the potential for organized severe convection could be displaced away from the strongest instability. Even so, instability is forecast to remain weak which appears to be the main limiting factor. ...Friday/Day 6 to Sunday/Day 8... On Friday, an upper-level trough is forecast to move northeastward into the north-central U.S., as moisture return takes place in western parts of the southern Plains. It appears that thunderstorm development will be possible across parts of west Texas within the northwestern part of a moist airmass. Large-scale ascent is forecast to remain relative weak suggesting that any severe threat could be isolated. On Sunday, southwesterly mid-level flow is forecast over the Great Plains, as low-level moisture advection continues. Scattered thunderstorms will be possible within this moist airmass as surface temperatures warm during the day. At this time, forecast instability and shear appear marginal for severe storms, and any organized convection should be relatively isolated. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sun Oct 27 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE CENTRAL PLAINS NORTH-NORTHEASTWARD INTO THE UPPER MISSISSIPPI VALLEY... ...SUMMARY... Isolated severe thunderstorms with hail and strong wind gusts, will be possible Tuesday night from the central Plains north-northeastward into the upper Mississippi Valley. ...Central Plains/Mid Missouri and Upper Mississippi Valleys... An upper-level trough is forecast to move eastward across the Desert Southwest on Tuesday. Southwesterly mid-level flow will be located between the western U.S. trough and an eastern U.S. upper-level ridge. This will help to maintain a broad belt of strong low-level flow across the Great Plains and Mississippi Valley. By Tuesday evening, surface dewpoints are forecast to reach the 60s F along a narrow corridor from the central Plains into the mid Missouri Valley. At the surface, a cold front is forecast to move southward into the central Plains, as a low deepens in southwestern Nebraska. Thunderstorms are expected to develop near the front from the evening into the overnight period as large-scale ascent increases ahead of the approaching trough. NAM forecast soundings ahead of the front from eastern Nebraska northeastward into southern Minnesota have 0-6 km shear steadily increasing from the evening into the overnight, with 0-6 km shear peaking in the 60 to 70 knot range late Tuesday night. Instability is also forecast to increase Tuesday night, with MLCAPE reaching the 500 to 750 J/Kg range. 700-500 mb lapse rates are forecast to reach 7 C/km in some areas. The environment should support isolated supercell development with a potential for hail. Storms that develop behind the front will likely be elevated. Isolated surface-based storms are also expected to the east of the front, where a few marginally severe wind gusts may occur. The limitation for this scenario is that much of the convective development is expected to take place overnight, when thermodynamics will not be as favorable. This may keep any severe threat localized and marginal. ..Broyles.. 10/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sun Oct 27 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE CENTRAL PLAINS NORTH-NORTHEASTWARD INTO THE UPPER MISSISSIPPI VALLEY... ...SUMMARY... Isolated severe thunderstorms with hail and strong wind gusts, will be possible Tuesday night from the central Plains north-northeastward into the upper Mississippi Valley. ...Central Plains/Mid Missouri and Upper Mississippi Valleys... An upper-level trough is forecast to move eastward across the Desert Southwest on Tuesday. Southwesterly mid-level flow will be located between the western U.S. trough and an eastern U.S. upper-level ridge. This will help to maintain a broad belt of strong low-level flow across the Great Plains and Mississippi Valley. By Tuesday evening, surface dewpoints are forecast to reach the 60s F along a narrow corridor from the central Plains into the mid Missouri Valley. At the surface, a cold front is forecast to move southward into the central Plains, as a low deepens in southwestern Nebraska. Thunderstorms are expected to develop near the front from the evening into the overnight period as large-scale ascent increases ahead of the approaching trough. NAM forecast soundings ahead of the front from eastern Nebraska northeastward into southern Minnesota have 0-6 km shear steadily increasing from the evening into the overnight, with 0-6 km shear peaking in the 60 to 70 knot range late Tuesday night. Instability is also forecast to increase Tuesday night, with MLCAPE reaching the 500 to 750 J/Kg range. 700-500 mb lapse rates are forecast to reach 7 C/km in some areas. The environment should support isolated supercell development with a potential for hail. Storms that develop behind the front will likely be elevated. Isolated surface-based storms are also expected to the east of the front, where a few marginally severe wind gusts may occur. The limitation for this scenario is that much of the convective development is expected to take place overnight, when thermodynamics will not be as favorable. This may keep any severe threat localized and marginal. ..Broyles.. 10/27/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Sun Oct 27 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE CENTRAL PLAINS NORTH-NORTHEASTWARD INTO THE UPPER MISSISSIPPI VALLEY... ...SUMMARY... Isolated severe thunderstorms with hail and strong wind gusts, will be possible Tuesday night from the central Plains north-northeastward into the upper Mississippi Valley. ...Central Plains/Mid Missouri and Upper Mississippi Valleys... An upper-level trough is forecast to move eastward across the Desert Southwest on Tuesday. Southwesterly mid-level flow will be located between the western U.S. trough and an eastern U.S. upper-level ridge. This will help to maintain a broad belt of strong low-level flow across the Great Plains and Mississippi Valley. By Tuesday evening, surface dewpoints are forecast to reach the 60s F along a narrow corridor from the central Plains into the mid Missouri Valley. At the surface, a cold front is forecast to move southward into the central Plains, as a low deepens in southwestern Nebraska. Thunderstorms are expected to develop near the front from the evening into the overnight period as large-scale ascent increases ahead of the approaching trough. NAM forecast soundings ahead of the front from eastern Nebraska northeastward into southern Minnesota have 0-6 km shear steadily increasing from the evening into the overnight, with 0-6 km shear peaking in the 60 to 70 knot range late Tuesday night. Instability is also forecast to increase Tuesday night, with MLCAPE reaching the 500 to 750 J/Kg range. 700-500 mb lapse rates are forecast to reach 7 C/km in some areas. The environment should support isolated supercell development with a potential for hail. Storms that develop behind the front will likely be elevated. Isolated surface-based storms are also expected to the east of the front, where a few marginally severe wind gusts may occur. The limitation for this scenario is that much of the convective development is expected to take place overnight, when thermodynamics will not be as favorable. This may keep any severe threat localized and marginal. ..Broyles.. 10/27/2024 Read more